Combination drum and belt sanding surfacing machines



July 21, 1959 J. A. NYLUND ETAL COMBINATION DRUM AND BELT SANDINGSURFACING MACHINES Filed June 5, 1957 4 Sheets-Sheet 1 NVENTORS.ATTORNEY COMBINATION DRUM AND BELT SANDING SVURFACING MACHINES FiledJune 3, 1957 July 21, 1959 J. A. NYLUND ETAL 4 Sheets-Sheet' 2IINVENTOR')l JOHN,- A. NYLUND FRAN K J. M I E H E lll-v v July 2,1, 1959J. A. NYLUND ET AL 2,895,262

COMBINATION DRUM AND BELT sANDING suRFAcING MACHINES Filed June 3, 19574 sheets-sheet s INVENTORS JOHN A. NYLUND FRANK J. MIEHE ATTORNEYS July21, 1959 J. A. NYLUND ETAL 2,895,262

COMBINATION DRUM AND BELT vSANDING sURFAcING MAcHNEs 4 Sheets-Sheet 4Filed June 5, 1957 INVENTORS JOHN A NYLUND FRANK J. MlEl-IE ATToR N EYQ;

COMBINATIN DRUM AND BELT SANDING SURFAOING MACHINES John A.NylunrL'Portland, and Frank J. Miehe, Lake Grove, Oreg.

Application June s, `19157, serial No. 653,152

4 claims. (ci. s1137) The present invention relates to combination drumand belt sanding surfacing machines, particularly those adapted to thesurfacing, sizing and smoothing of plywood, sheet steel and the like.

The primary object of the invention is to provide a 'surface sandingmachine including an endless sanding belt having a fast cutting stationand a smoothing station arranged in spaced relation so that fast cuttingand smoothing are accomplished by the same belt successively on the workon a single pass through the machine.

Another yobject of the invention is to provide means directing the workover the sanding belt at a slight angle thereto, preventing striationsbeing-formed on the work .being sanded.

A further object of the inventiony is to provide a resilient pressurebar for applying pressure to the back of the sanding belt while sandingthe surface of the work, means being provided for adjusting therresilient pressure p ad tovarious kinds and types of work.

. Another object of the invention is to provide a combination of asanding drum with a sanding belt assisted by a resilient pressure padfor governing the operation of the sanding belt in relation to the workbeing processed.

A further object of the invention is to provide a means of causing asanding belt to maintain a centralized I running position over a drivingdrum and associated idler drums in its operation.

, A still further object of this invention is to provide means forstarting work over the sanding belt, drum and`^ pressurebar withoutbeveling or contouring the leading edge of the work onirst entering theposition for sanding or surfacing. The above action also applies ywhenthe trailing edge of the work being processed leaves contact with theIworking area of the sanding drum, belt and pressure bar.

' Another object of this invention is to provide a pressure applicatorbehind the sanding belt, consisting of a revolvable cooled roller,particularly adapted for high Aspeedprecision grinding and finishing.

Other objects and advantages 'will become apparent Iin .the followingspecification when considered in the llight of the attached drawings, inwhich:

Figure 1 is a side view of this new and improved combination drum andbelt sanding machine, parts broken away for convenience of illustration.

Figure 2 is a transversesectional view, taken on the `line 2 -2 ofFigure l, looking in the direction indicated, parts broken away forconvenience of illustration.

. Figure 3 is a horizontal sectional view, taken on the line 3-3 ofFigure 1, looking in the directionindicated.

Figure 4 is a fragmentary horizontal sectional view,

A United States Patent O 2,895,262 Patented July 21, 1959 taken on theline 4-4 of Figure 1, looking in the direction indicated.

Figure 5 is an enlarged fragmentary sectional view, taken on the line5-5 of Figure 6, looking in the direction indicated.

Figure 6 is a horizontal sectional view taken on the line 6 6 of Figure5, looking in the direction indicated.

Figure 7 is an exploded fragmentary perspective View of the pressure barand the resilient pad.

Figure 8 is a diagrammatical plan View showing the work passing over thesanding belt under the work feeding mechanism, illustrating theprinciple of feeding the work over the sanding belt at a slight angle.

Figure 9 is a schematic layout of the electric and mechanical controlfor maintaining the sanding belt in alignment over the sanding drum,pressure bar and idler rollers.

Figure 10 is a longitudinal cross-section similar to Figure 5 of amodified form of sanding belt pressure applicator.

The new and improved combination drum and belt sander indicatedgenerally by the reference character S includes a base frame F. Fixedlymounted within the frame F is a sub-frame SF and mounted upon the uppersurface of the base frame F is a work feeding assembly M.

The base frame F preferably includes a vertical web 10 mounted on a base11. Extending transversely of the sander S are webs 12. The finishedbase frame F being of box-like structure. Access is obtained by way ofthe open side 13 of the frame F.

The sub-frame SF consists of parallelly disposed legs 14 and 14 joinedby a web 15. The sub-frame SF is secured to the vertical web 10 of thebase frame F by feet 16, which are formed integral with the side frame14. of the sub-frame SF, as best illustrated in Figures 2 and 3. Thefeet 16 have flanges 16 formed thereon and bolted to the leg 10 of thebase frame F by bolts 17. According to the above method of mounting theframe SF within the base frame F, a cantilever system of mounting theframe is achieved permitting free entry from one side of the base frameF for ease of servicing.

Extending between the legs 14 and 14 of the subframe SF is a horizontalweb 1S. The web 18 provides a base for supporting a U-shaped bracket 19,referring particularly to Figures l and 2. The bracket 19 supports theidler belt roller 20. A base 19 of the U-shaped bracket assembly 19 ispivotally mounted to the web 18 by a hinged connection 21.

' The hinge connection 21 includes an eye bolt 22, secured to the web 18and ears 23 forming part of the base 19 positioned on opposite sides ofthe eye bolt 22 and pivotally secured thereto by a pivot bolt 24. Thebase 19 is maintained in a level position in regard to the web 18 bydownwardly extending rockers 25 which form part of the base 19. Thelower ends of the rockers 25 ride on the web 18, permitting the Ushapedbracket 19 to be rocked about the eye bolt 22, and at the sam'e timemaintaining the structure 19 in a level transverseposition on the sanderS. The operation of which will be further described later on.

A shaft 26, forming part of the idler roller 20 is journalled within aself-aligning bearing 27 iixedly mounted to upper end 28 of an upwardlyextending leg 2 9 forming part of the U-shaped bracket assembly 19. Theopposite end of the roller 20 has a stub shaft 30 journalled within aself-aligning bearing 31 mounted upon a vertical threaded shaft 32.

The shaft 32 is journalled at its opposite end portions in spacedbearings 33, 34 forming part of an upwardly extending leg 35 of theU-shaped bracket 19. A worm wheel 36 is threaded on the shaft 32 andoperates between asse-.262

bearing-33 and bearing 34. A worm 37 drives the worm wheel 36 from areduction `gear box 38 forming part of a motor 39, referring to Figures1, 2 and 9.

The motor 39 is .mounted to Ithe base member 19 of the U-shaped bracketassembly 19. When the motor 39 operates in one direction it will raisethe bearing 31, together with the end 20 of the idler roller 20 and whenoperated in the opposite direction the bearing 31 will be lowered. Thereason for this movement is to maintain a sanding lbelt 47 in alignmentwith a sanding drum 40, the idling drum 20 and a driving drum 41 by anautomatic means to be described later on.

The sanding drum 4t) is journalled within bearings 42 mounted lto theside frames 14 and 14 of the sub-frame SF. The bearings 42 remainstationary at all times. The driving drum 41 has its shaft 43 journalledwithin bearings 44 mounted to the lower ends of the side frames 14 and14'. The shaft 43 may 'be driven by any suitable means through a sheave45, which in turn may be driven by driving belts 46 from a source ofpower (not shown).

The sanding belt 47 is trained over the driving drum 41, the sandingdrum 40 and over the idler drum 20. The belt 47 is maintained in a tautcondition by the action of spring loaded plunger 48, which is pivotallymounted to a cross member 49 connecting the legs 29 of the `U-shapedbracket assembly 19 through ears 50, which have the end 51 of a plunger48 pivotally connected thereto by a pin 52.

The spring loaded plunger 48 operates within a tubular member 53, whichhas one of its ends pivotally mounted to a crank 54 at 55. The crank 54forms part of a shaft 56 which extends between the side frames 14 and 14of the sub-frame SF. The shaft 56 is journalled within the frames 14, 14and is rotated by a lever 57, which is show-n by full and broken linesin Figure 1, and in full lines in Figure 3.

In Figure 1, it will be noted that the pivot point 55 is past the centerline of the tubular element 53 and the spring lloaded plunger 48. Thismounting maintains the pressure of a spring 58 against a shoulder 59 ofthe tubular member 53 and a shoulder 66 of the plunger 48', which forcesthe arms 29 of `the U-shaped bracket 19 towards the belt 47, maintainingthe bel-t 47 in a taut and tight condition. The movement of the pivotpoint 55 beyond the center line above referred to, is limited by thelever 57 contacting an outwardly extending stop 57',

The eye bolt 22 permits the forward movement of the arms 29 about thepivot pin 24 towards the belt 47. When the lever 57 is moved in thedirection of the arrow, it will pull the arms 29 carrying the tighteningrolle1` 20 away from the belt 47 so that the belt 47 can be removedthrough the open end 13 of the base frame F, referring particularly toFigures l and 3. Being able to remove the belt 47 through the open end13 of the base frame F is one of the features of this sander S.

Mounted transversely to the upper ends of the side frames 14 and 14 is apressure bar 61. The bar 61 has a pressure strip 62 lixedly securedalong its upper edge 63 by suitable means, best illustrated in Figures5, 6 and 7. The pressure bar 61 is positioned in parallel closely spacedrelation to the sanding drum 40l and serves to hold the sanding belt 47against the work for a smoothing or a polishing action following theheavy cutting action of the drum 40.

The pressure bar 61 is slidably mounted within a transverse supportingbeam 64 mounted to the upper ends of the frames 14 and 14 lby legs 65.The transverse beam 64 is U-shaped in cross-section, as best illustratedin Figure 5, and has a reversed tongue 66 formed along one of its edges.The tongue 66 operates within the longitudinal groope 66 of the pressurebar 61. The lower edge 66 of the pressure bar 61 is disposed at an angleto the transverse plane of the sander S, as best illustrated in Figure6, the tongue 66 and groove 66' are disposed parallel to the lower edge66" and at an angle to thetransverse plane of the sander S.

A threaded rod 67 formsf part of one end of the pressure bar 61 and isadapted to be moved endwise by a hand wheel 67. When this is done, dueto the angle of the lower edge of the bar 61 and the tongue 66, theupper edge of the bar 61 will be raised and lowered in reference to thesanding belt 47 while remaining parallel to the sanding drum 40.

Referring to Figure 5, the pressure strip 62 includes an elongatedretaining clip 62" having one edge engaged over the upper edge of thepressure bar 61, and its opposite edge engaged in a groove 68 formed inthe pressure bar 61. The pressure strip 62 may be made of resilientmaterial, a semi-resilient material or a hard material, or a combinationthereof, depending upon the material being surfaced.

The pressure pad 62 includes a resilient or semiresilient strip 62resting upon the elongated clip 62". The resilient strip 62" is furtherencased within the elongated strip material 62. Both the wearing strip62' and the base clip 62"' have their edges brought together at 63 andclipped together by an elongated clip 63". The edges of the strip 62 andclip 62"' are brought around in return bends to slip over the upper edgeof the pressure bar 61 entering on one side a groove 68 and at the otherembracing the side 68 of the bar 61, as best illustrated in Figure 5,maintaining the pressure pad 62 in place so as to be removed or placedon the pressure bar 61 in an assembled condition.

Extending transversely of the base frame F on its top are bed platesupports 69, forming part of the webs 12 of the base F. Adjustablymounted on the bed plate supports 69 are bed plates 70 extending thecomplete width of the sander S. The plane of the bed plate support 69and the longitudinal plane of the bed plates 70 lie at an angle to thehorizontal plane of the sander S. This plane tends to slope upwardlytowards the center line of the sander S, as best illustrated in Figures1 and 4.

The -bed plates 70 have slots 71 formed in their upper surface in whichcap screws 72 engage and are threaded into the bed plate supports 69 sothat the height of the upper plane of the surface of the bed plate 70can be varied in reference to the upper surface of the sanding drum 40and the belt 47. On moving the bed plates 70 towards the center of thesander S, the upper surface of lthe bed plate 70 will be raised and onmoving the bed plate 70 away from the center of the sander S, the uppersurface of the bed plates 70 will be lowered.

We will now describe the work feeding assembly M, which includes thefeeding mechanism for feeding the work to be sanded over the bed plates70 and over the sanding belt 47. A rectangular frame 73 is supported oneach of its four corners by threaded screw jacks 74. The screw jack 74passes through supporting bearings 75 which are centered on the screwjack 74 by collars 76.

The lower ends of the screw jacks 74 are threaded into their supports,consisting of ears 77, which form part of the four corners of the baseframe F, referring particularly to Figures 1, 2 and 4. There are fourthreaded screw jacks 74, one located on each corner of the sander S. Thethreaded jacks 74 are geared together by any suitable means, as forinstance sprocket chains 78, which couple one set of jacks 74 on oneside of the sander together, while the transverse chain 79 connects bothsets of jacks 74 located on both sides of the workfeeding assembly M.

Referring to Figure 2, one of the vertical screw jacks 74 may have acrank 80, adapted to be connected thereto for rotating the jacks 74,which in turn wil-l rotate all of the jacks 74, raising the frame 73vertically or lowering the same for maintaining the same on a parallelplane with therbed plates 70; Transverse rollers 81 and 81' arejournalled within bearings 82 and 82 xedly mounted to the frame 73.

A feed belt 83 of resilient material is `trained about the rollers 81and 81' and under a tightening roller 84, which is journalled to one endof arms 86 by bearing 85. The opposite end of the arm 86 is journalledto the shaft 84 of the roller 81. The shaft 84' and the roller 81' aredriven through a gear reduction box 87 driven by a motor 88, thereduction gear box 87 and motor 88 are mounted upon an outwardlyextending base bracket 89 forming part of the frame 73, referring toFigure 2.

The roller 84 is driven by the driving roller 81 by inter-meshing gears84". The roller 84 maintains the feeding belt y83 in a working tautcondition. The more resistance offered to the movement of belt 47 thegreater will be the pressure applied to the roller 84 by the roller 81due to the action of the driving gears 84".

A feed belt backing plate 90 is iixedly secured between the side framemembers 73 by cap screws 91. A transverse concave portion 92 extendstransversely of the lower surface of the backing plate 90 above theposition of the pressure pad 62. The object of this relief is to allowthe leading or trailing edge of the Work 94 to pass thereunder withoutforcing the edge down against the sanding belt 47, leaving a squareleading and trailing edge to the work 94.

The work 94 is fed through the sander S in the direction of the arrow,referring particularly to Figures 1 and 8. In Figure 8 the outline ofthe work feeding assembly M is indicated by broken lines and square withthe direction of travel of the work, while the boundaries or line of thesanding belt 47 is indicated in full lines in an exaggerated angle tothe direction of travel of the work 94. As a matter of fact this angleis very slight, but it prevents striations on the face of the work beingsanded and polished.

To maintain the sanding belt in a central position over the drivingroller, sanding rollers and idlers, the following mechanism is employed,referring particularly to Figure 9. The raising and lowering of thebearing 31 by the action of the motor 39, worm 37, worm wheel 36 and thevertical threaded shaft 32 which raises and lowers the idler shaft 20relative to the bearing 27, will carry out the object of centralizingthe sanding belt 47.

The motor 39 is a reversible motor and is controlled from a reversingswitch 95 by switches 96 and 97 located adjacent the edges 47 of thesanding belt 47 The switches 96 and 97 are operated in the followingmanner. A jet of air is directed from nozzles 98 and 99 from a sourcenot here shown, towards the pivotally mounted switch vanes 96 and 97.When the belt 47 is running in a central position, this air contacts theswitch vanes 96', 97', opening their contacts 96" and 97, causing thereversing switch to be in open position and the motor 39 at astandstill, but when the sanding belt 47 moves to one side of the rollerassembly, as shown in Figure 9, the air delivered from the nozzle 99will be interrupted by the belt 47 and the switch =87 will be moved tothe position shown, -by a spring 100 closing the contact 97, energizinga solenoid 10'1 of the reversing switch 95 completing an electriccircuit through the motor 39, which will continue to operate in onedirection until the belt 47 returns to its position between the nozzles98 and 99, when the switch vane 97 will be opened by this stream of air.

When the motor 39 was energized, it either raised or lowered the bearing31 by driving the worm gear 36, threading the jack screw 38 either up ordown, which in turn raised or lowered one end of the idler roller 20,

shifting the belt 47 in the opposite direction. The same action takesplace when the belt 47 moves in the direction opposite to that abovedescribed, only that the solenoid 102 of the reversing switch 95 will beenergized, causing the motor 39 to operate in the opposite direction,which will lower the bearing 31 causing the belt 47 to recenter itselfagain.

Referring to Figure 10, a modified form of pressure pad is illustrated,which consists of a horizontal drum or roller 103 journalled to brackets103a forming part of the pressure plate 61. This form is used preferably.for high speed finishing work, and is cooled by circulating a coolinguid 105 therethrough. In the operation of a `high speed sanding belt 47over the roller or pad, heat is developed within the same, therefore acooling medium is used to carry this heat away from the pad.

The operation of this new and improved combination drum and belt sandingsurfacing sander S is as follows. The elevation of the bed plates 70 arefirst adjusted in regards to the elevation of the sanding drum and beltto correspond to the depth of cut to be made in the work 94. Theelevation of the polishing and finishing pressure pad 62 is thenadjusted -by a hand wheel 67', referring to Figures 5 and 6particularly. The object of this adjustment is to apply the properamount of pressure against the back of the sanding belt 47 to effect thedesired smoothness and finishing of the work 94.

The elevation of the work feeding mechanism M is then adjusted by thejack screws 74, as by the rotation of the crank indicated in brokenlines in Figure 2, to correspond to the thickness of work 94 to Ibeprocessed through the sander S. The work 94 is fed in as viewing Figures1 and 8 under the feeding belt 83 and over the bed plates 70 in thedirection of the arrows.

By referring particularly to Figures 5, 6 and 7, the design of the pad62 is such that it is completely selfcontained and can be removed andreplaced from the pressure plate 61 when necessary.

The principles involved in this sander S are of such a nature that theworking parts of the sander S can be used in tandem with the presentdisclosed sander S for sanding both sides of the work.

When it becomes necessary to remove or replace the sanding belt 47,referring to Figures l, 2 and 3, the lever 57 is moved in the directionof the arrow, moving the idler roller 20 towards the sub-frame SF,permitting the belt 47 to be removed out the open end 13 of the baseframe F.

Having thus described the preferred embodiments of the invention, itshould be understood that numerous structural modifications andadaptations may be resorted to without departing from the scope of theappended claims.

What is claimed is:

l. A sanding machine comprising a base frame having a pair of upstandingspaced parallel webs, a single upstanding web secured to said base andextending between adjacent ends of said parallel webs, a sub-framesecured to said single upstanding web between said parallel webs, meanson said base frame for feeding work horizontally throfugh said machine,a roller journalled on said subframe with its axis perpendicular to thedirection of travel of work through said machine, said roller having itsperipheral surface positioned closely adjacent the work feeding throughsaid machine, a second roller spaced from said first roller andjournalled on said sub-frame with its peripheral surface spaced belowthe work feeding through said machine, a third roller journalled on saidsub-frame intermediate said first and second rollers and spacedsubstantially therebelow, said rollers having their axes substantiallyparallel, a work contacting sanding belt trained over said rollers, saidrst named roller supporting said sanding belt in initial work contactingposition, means controlled by the position of said belt on said rollersfor tilting said second roller to move said belt to a central positionwith respect to said roller, a resilient pressure bar positionedadjacent said rst named roller between said first and said second namedrollers supporting said sanding belt in a secondary work contactingposition and manually operated means connected to said pressure bar forvertically adjusting said pressure 7 bar` with respect to the Workfeeding throughsaid machine.

2. A deviceas claimed in claim 1 wherein the means feedingwvork acrosssaid sanding beltA includes an endless belt positioned above said baseframe in opposed rela,- tion to said sanding belt.

3. A device as claimed in claim 1 wherein the manually operated meansincludes an elongated cam support engaging said pressure bar forvertical adjustment.

4. A device as claimed in claim l wherein the means feeding Work incontacting relation to said sanding belt includes a conveyor beltarranged in spaced parallel relation to said sandingbelt.

References Cited in the file of this patent UNITED STATES PATENTS HoddMay 17, CoX Apr. 9, Williams Sept. 19, Pinkney Nov. 28, Johnson Dec. 15,Hercik Feb. 24, Roth et al' Nov. 23, Illmer et al. Ian. 4, Martin et alDec. 16, Gifford Apr. 26,

Conley Jan. 31,

